Anybody else never gotten an efficient diode?

[grainde]

Hey Wannaburn my PL 520 was quite inefficient and gave 84 mW at 275 mA. Most people were getting over 100 mW at that current. Im writing to let you know that mine just died or dropped to 18 % of its original output. Its still lasing and I still have a collimated beam and very bright spot, but on my LPM Im only getting 12 - 15 mW with a G2.

The wavelength also looked identical to my 532's so Im guessing maybe the diode couldnt handle it?

Anyway just a heads up if you want to reconsider the 300 mA current you are using. I know these diodes are very new and there is very little data available on safe operating currents and longevity...:thinking: :beer:


Edit: Another word of warning @ Wannaburn!! I just read you are waiting to make a 9 mm build. I happened to have completed 3 builds over the weekend...One of them was the 520 which is now for all intents and purposes dead, but the other was a 9 mm. That died too :cryyy: I was using one of Foulmists drivers set at 2.4 A and more than likely had a short between the copper base and my heatsink. I was using arctic silver and the laser worked irratically for an hour or so turning on then refusing to and the output was very low. I may have also had a dud 9 mm, but I dont think so. Anyway it passed with only 20 seconds of use. Im also rather upset about having thrown $230 out the window... Have a look at Foulmists thread on the V3 if you plan on using that. :beer:

 

[Blord]

I have noticed that the newest batch projectors have much better efficiency diodes than the same projector from the last year. The manufacture methods must have improved over time to yield much better diodes.

 

[grainde]

I thought DTR said the diodes had been selected ie Ca$1o had tried to save money by using some better diodes in certain areas of the array and worse ones elsewhere? I know this was the case for the M140's but Im unsure whether they have done this for the 9 mm projectors? :thinking: :beer:

Also if any one has any suggestions on what to do with my 520 above Im all ears....?

 

[Leodahsan]

I have noticed that the newest batch projectors have much better efficiency diodes than the same projector from the last year. The manufacture methods must have improved over time to yield much better diodes.

The actual projectors have 18 diodes (outputting 2.22W each, for 40W total), but the sled is slotted to fit 22 diodes. Maybe when the projector was developed, the diodes rating were 1.81W (so 22 pieces achieves 40W), and the sled were designed for 22 pieces... Now the diodes have better efficiency and maybe its correlated to the lower number of diodes found in the projectors now... just my 2 cents...

 

[BowtieGuy]

I've got real lucky with my 9mm diode from DTR, it's giving me 2.8W+ with an x-drive preset at 2.1A!

On the other hand, I've had s**t for luck with most of the green modules I've gotten.

Win some, lose some. :beer:

 

[cheech226]

Jesus just tell me how much I gotta pay to NOT get an underperformer. I would rather make one goddamn laser and have it turn out awesome, than make 10 mediocre ones!!! And to think I thought it was random. Luck of the draw, as they say. Frankly I am a little dissapointed. If you are going to cherry pick and sell at alternate prices, be up front about it so people don't waste tons of their damn money trying to "luck out on one". Kind of irritated here.

Ah, grasshopper, it's not really the numbers, but the beauty of the beam.

 

[IsaacT]

I agree, and I am mostly a single moder, but more power equals higher visibility. And that I are about.

 

[DTR]

I agree, and I am mostly a single moder, but more power equals higher visibility. And that I are about.

Well food for thought on that. Not that it is of much consolation to someone when they get a less than efficient diode but testing has shown that efficiency and wavelength are inversely proportional. Meaning lower efficiency diodes are higher in wavelength and higher efficiency diodes are lower in wavelength. It has to do with how much waste heat the diodes are making and as we know temperature has a great effect on wavelength.

This is why say with a 2.8W 9mm being pushed to 2.56A and a 3.5W 9mm at the same 2.56A will probably have about the same visual brightness. See this example.

Say the 2.8W diode is 450nm and the 3.5W is 445nm. The visual brightness would be about the same at least according to this tool.
Dot: (450nm 2800mw) vs. (445nm 3500mw)


I have always believed that efficiency is just for bragging rights on a LPM and not really a meaningful measure of a diode. It depends on what you are looking for. Now this does not speak for a diode that is under efficient to the point of being a defect or damaged.

 

[Leodahsan]

I think efficiency is ranked by nichia.

Read carefully this...

It is for the 9mm diodes.

Any thoughts?

 

[midnighttattoo]

my most recent sjo6 is 425 mw at 450ma with three element
is this about right ?
so tempeted to crank it but gunna resist

 

[DTR]

I think efficiency is ranked by n!ch!&.

Read carefully this...

It is for the 9mm diodes.

Any thoughts?

They are definitely ranked by the manufacturer but we have no idea what ones the projector companies buy. I could be specific or they could get all ranks and space them specifically in the arrays.

my most recent sjo6 is 425 mw at 450ma with three element
is this about right ?
so tempeted to crank it but gunna resist

Yep pretty normal. 400mW-500mW with a three element lens is right on @ 450mA.:beer:

 

[SixTee9]

If one was to buy a projector with the 445nm 9mm diodes what brand and model number projector would that be?

 

[Moe Ron]

Greetings,

Seems like the 9mm diodes nowadays average from 2.6w to 2.8w at 2.2a to 2.4a current. I have 2 recent builds that are about the same in output, one with the new X driver from Angelos and the other using a 4 mode led driver. Both set at 2.4a.
Have not yet been lucky enough to get a diode running at 3.5w or somewhere close. Then again I have only built a few so I am sure will eventually get a really efficient one.

cheers,
Moe

I've got real lucky with my 9mm diode from DTR, it's giving me 2.8W+ with an x-drive preset at 2.1A!

On the other hand, I've had s**t for luck with most of the green modules I've gotten.

Win some, lose some. :beer:

 

[Pi R Squared]

Well, still waiting on my MS-SSW host to come in the mail so I can try out my new 9mm Diode, hopefully Luck decides to be a Lady and not the whor* she usually is.

You do need some luck to get a lady, you only need money for a whore.:crackup:
I hope you have better luck with your next build.

 

[midnighttattoo]

just had a 9mm that didn't make 2w @2.2 but still a very powerful laser.

I wonder if nichia would bother grading them if they supplied a mixed lot to projector manufacturers.
Id like to know where the top notch stuff goes !

 

[DTR]

just had a 9mm that didn't make 2w @2.2 but still a very powerful laser.

I wonder if nichia would bother grading them if they supplied a mixed lot to projector manufacturers.
Id like to know where the top notch stuff goes !

Please keep in mind you are using a three element glass. You will want to go to a G-2 or stock 9mm lens. Based on the power you said it does in your PM it will probably do close to 2.5W with a G-2 or stock 9mm lens using a three element lens is about 25% less power. So that would be 1875mW after the losses from the lens. So your diode is normal efficiency.:beer:

Greetings,

Seems like the 9mm diodes nowadays average from 2.6w to 2.8w at 2.2a to 2.4a current.

cheers,
Moe

Nothing has changed from nowadays from the beginning. If you look at the original 9mm thread and testing Lazeerer did on them that pretty much is on par. I have always found the average @ 2.2A to be 2.4W-2.8W if they are outside of that they are the rare super efficient or the rare underperformers. Rick has stated he only finds one 3.5W diode in each projector of 24 diodes so they are very rare.:beer: